There is probably no single woodworking health or safety issue that is kept more "silent" than dust ingestion. Only in recent years has the woodworking community started to take their respiratory health quite seriously. Wood dust is now classed as carcinogenic by many authorities around the globe, so it is even more important than ever to make sure your lungs are protected from breathing in harmful dust particles.

Often you cannot see the dust in the air, and by this stage, the chance of catching it is less than if it is caught at the source. So today, we are going to look at another vacuum-type dust extraction machine designed to catch dust at the source, and to clean up later if needed. Regular readers may recall we reviewed a Festool extractor fairly recently as well.

The product is the Karcher 361 Eco TE, and we specially selected this model from their range as it offers features that are most suited for use with woodworking tasks and tools.

Packaging and Assembly
We received the 361 Eco TE boxed and partly assembled. Once you extract the various components, manuals and miscellaneous bits and pieces, you can start to assemble the unit. Actually, assembly is almost a no-brainer as all you need to di as attach the pivot wheels to the front of the unit (they push in) and attach the larger main wheels at the rear (no tools required). Once the wheels are on, simply attach the tool holding components to the back and assemble the various rods that make up the upright vacuum handle (if needed). Pretty easy stuff. The manual outlines assembly requirements if you are not the world's best machinery or tool assembler.

Manual
The printed manual outlines all assembly, operation instructions and specifications for the tool. It is printed in just about every language known to humans, except perhaps Egyptian hieroglyphics! The line-art type drawings are very clear and instructions are direct and to the point, which helps eliminate any possibility of confusion. Take particular note of the instructions because many of the features of this unit have specific instructions for use. Also take note of the machines specifications and maximum connected tool wattage allowable.

Specifications
And speaking of specs, here are the listed specs for the Karcher NT361 Eco TE dust extractor:

• Motor - 1200W (normal operation) - 1380W (maximum/peak)
• Collection Capacity - 34 Liters
• Air Volume Moved - 56 Liters/sec (max)
• Hose Diameter - 35mm
• Pressure - 235 mbar (max)
• Sound Emission - 63 dB
• Cord - 7.5m long, 15A plug
• Weight - 9.5 kg

*Note, motor specifications and electrical connection for models sold in the USA, and other parts of the world may vary accordingly.

As you can see from the above list, the Karcher NT361 TE features a 1200W motor and can consume 56 liters of air per second. In qualitative terms, these figures really suck! I'm speaking literally here, the NT361 TE has very good suction capabilities that exceed many other similar vacuums and shop-vacs of similar size. In testing, we found little tendency for the machine to lose suction, except when the bag was perhaps reaching 90% or more capacity, but this is to be expected. We hooked the NT361 TE up to numerous tools in the workshop during the test period and dust extraction performance seemed to be very good. it is hard to judge just how efficiently the unit works because some power tools are designed better than others in regard to dust extraction. However, one tool with very good dust extraction features is the Festool OF1400 EBQ router, and when hooked up to this tool, the NT361 TE left almost no sign of dust or debris in trenching work, and performed similarly well on edge profiling work using the Festool's chip deflector attachment.

The hose features a tapered end connector which offers the user quite a good range of inside and outside connection diameters. This combination allows the hose to be hooked up to any tool with the following dust port diameters (in millimeters);

• 21.5, 26, 26.9, 31, 32, 35.

Given that the end connector is also made of rubber, there is some flexibility to adapt to dust collection ports with diameters close to those figures as well.
The NT361 Eco TE also ships with some standard vacuum rods and accessories so the unit can be used for everyday vacuuming tasks, or for general cleaning of the workshop. These attachments are shown on the image at the top of this review and in images in the right column. We used the unit on routers, hand-held sanders, for collection on the bandsaw, and on the biscuit joiner, among others. Perhaps it was just luck that the multi-stepped connector fit all these tools with no additional attachments required?

A 34 liter collection capacity is a good size for a shop-vac. Not so small that you have to be changing collection bags every day, but not so large that it makes the machine difficult to cart around the workshop. The package comes with one collection bag. To fit it you must remove the top cover of the 361 by unclipping two latch clips, one of each side of the unit. The whole top assembly then just lifts off to expose the motor, filter, and collection space. You then just attach the collection bag into the base of the unit and it is a simple push-fit. Naturally, you do need to buy the bags from Karcher that will fit the vacuum port. These are sold in lots of five. Depending on how much woodworking you do and what tools you use the vacuum on will determine how quickly the bag fills up. The bag catches almost all the dust and chips. Naturally, some really fine dust will find its way through, and this is where the in-built filter comes into play. This fine dust will be captured by the air filter before the air is exhausted from the machine back into the ambient air. Karcher claims a dust retention figure of greater than 99.9%. I simply don't have a laboratory or test equipment to confirm this. My best effort was to place a direct halogen light source over the exhaust air stream to see if I could spot any dust particles being emitted from the machine. Even so, it was difficult to see any, and that air could possibly be contaminated by air ambient dust floating in the workshop air anyway. I think in this case, we will just have to take Karcher's word for it in this instance. I certainly did not experience any noticeable dust ingestion problems when using the extractor with tools I know would give a problem without dust extraction in place.

Cleaning the air filter is a simple process. Just position the red filter clean slider on the top of the unit in the down position. Now push the trigger on the end of the hose down and hold it for a few seconds. This directs air over the top of the filter and pulses air bursts to help push fine dust off the filter surface itself. It seems to work well in use and should be done after heavy vacuum loads or at least once per day during normal use. Because of its simplicity, compliance is almost a certainty. It is one of the nicer features on the 361 Eco TE model.

The best feature however, and one that should be on ANY vacuum or vacuum extractor you buy, is the integrated power outlet. Simply plug in your power tool (up to the maximum wattage approved in the manual for your country) and the extractor will turn itself on and off in accordance with your power tool. For example, when I plug a router into the extractor's power point, and then turn on my router, the extractor will switch itself on automatically. There is a small delay so as to not overload the circuit from the electrical burst that occurs in the milliseconds of tool startup. Once I switch the router, or any other power tool attached off, the vacuum continues on for around 15 seconds to ensure all dust is extracted from the hose and from around the tool's dust port. Naturally, the advantage this offers is that you do need to manually turn on two devices, and two two off separately. From a convenience and time standpoint, it is a real winner. On the unit we tried, the minimum connected tool wattage is 100W, and the maximum was 2200W, but again, check the manual for your country as these figures vary depending on your power supply. The green lamp next to the power outlet will light up when a tool is plugged in as a visual indicator to the user. The large top grey push button that can be seen in the images to the right is the main ON/OFF switch for the 361 Eco TE.

When it comes to sound emission, the 361 Eco TE gives off 63 decibels (dB). This is a very comfortable sound level for a unit of this size, and is 9 dB less than the Festool model we have reviewed previously. I'm waiting for the day that someone comes out with a 'silent' dust extractor, but I think I'll be waiting a little while yet, but the lower sound emission from the Karcher extractor is certainly very welcoming, and one of the quietest extractors I have seen so far. I do not feel a need to use ear plugs during general cleaning tasks with this unit, however, if you have those ear muffs with radios built in, why not enjoy the music :)

Mobility wise, the Karcher NT361 Eco TE features four wheels. Two smaller pivoting wheels at the front of the unit, and two larger, non-pivoting wheels at the back. Dragging the unit around the shop is generally not a problem, although we found the Festool model was a little smoother. Nonetheless, the 361 is very mobile, and can of course be easily picked up and carted around if needed. Its weight of 9.5kg (roughly 21lb) should not be too much of a problem for most and a top-mounted handle provides for an easy lift. The 7.5m (25 ft) power cord reduces the need for extension cords and can be wound around the back of the unit to keep it neat and compact. The hose can be attached and removed easily as well.

In the Shop
As mentioned above, this unit has great application for woodworkers. While the larger high volume, lower pressure dedicated dust extractors are a must in the workshop, the humble roll-around vacuum systems are just as important for catching dust from hand-held power tools and stationary machines that have smaller dust ports. We used the Karcher extractor attached to a home-made router fence and it did a great job of collecting most of the dust and debris above the table. It would be good if there was some type of "Y" junction attachment available for this unit that allowed you to use two hose sections simultaneously. One for collection above the router table, and one for the dust port on the router itself. I am not aware of such an accessory for this unit at this stage.

If you are looking to improve the dust collection capabilities of your workshop, and thus, greatly improve your respiratory health and save lots of time in shop cleanup, a vacuum-type extraction unit along the lines of the NT361 Eco TE would be well-worth considering. Whatever you buy, make sure it has the integrated power tool port, a good size dust capacity and good quality filters. Look for a model with lower sound emissions too.

I was quite happy with the performance of the Karcher NT 361 Eco TE. It certainly matches the Festool model in terms of extraction potential, and achieved this with a lower sound emission. On the flip side, the Festool does have more accessories available for it that are useful for woodworkers (including anti-static hose) and does move around a little better. In saying that however, I think both models would please the woodworker looking to capture more dust at the source.

The Karcher NT361 Eco TE is certainly an industrial quality vacuum system, and the price reflects this at around, or a little under AUD$999.00. Given its performance and features, this model is certainly a case of "you get what you pay for".

The Karcher NT361 Eco is also available in the USA and retailed through Tornado Industries Corporation.

Note that the non-TE model of the NT361 can also be used for wet-vacuuming purposes. The TE model is for dry vacuuming tasks only.